KR102620538B1 - Imaging Lens System - Google Patents

Abstract

The imaging optical system according to the present invention includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens, which are sequentially arranged at intervals from the object side, The object side of the fourth lens or the object side of the fifth lens is concave, and the F-number is 2.0 or less.

Description

Imaging Lens System

The present invention relates to an imaging optical system including a 7-element lens.

A small camera is mounted on the wireless terminal. For example, a small camera is mounted on the front and back of the wireless terminal, respectively. These small cameras are used for a variety of purposes, such as outdoor landscape photography and indoor portrait photography, so they require performance that is comparable to that of general cameras. However, small cameras are limited in mounting space by the size of the wireless terminal, making it difficult to achieve high performance. Therefore, there is a need to develop an imaging optical system that can improve the performance of small cameras without increasing the size of the small cameras.

For reference, prior art related to the present invention includes Patent Documents 1 to 3.

US 2019-0025549 A1 US 2016-0062086 A1 US 2016-0241756 A1

The present invention is intended to solve the above problems, and its purpose is to provide an imaging optical system capable of realizing high resolution.

The imaging optical system according to an embodiment of the present invention for achieving the above object includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens, which are sequentially arranged at a distance from the object side. , and a seventh lens, wherein the object side of the fourth lens or the object side of the fifth lens is concave, and the F-number is 2.0 or less.

The present invention can improve the performance of small cameras.

1 is a configuration diagram of an imaging optical system according to a first embodiment of the present invention.
Figure 2 is an aberration curve of the imaging optical system shown in Figure 1
3 is a configuration diagram of an imaging optical system according to a second embodiment of the present invention.
Figure 4 is an aberration curve of the imaging optical system shown in Figure 3
5 is a configuration diagram of an imaging optical system according to a third embodiment of the present invention.
Figure 6 is an aberration curve of the imaging optical system shown in Figure 5
7 is a configuration diagram of an imaging optical system according to a fourth embodiment of the present invention.
Figure 8 is an aberration curve of the imaging optical system shown in Figure 7
9 is a configuration diagram of an imaging optical system according to a fifth embodiment of the present invention.
FIG. 10 is an aberration curve of the imaging optical system shown in FIG. 9
11 is a configuration diagram of an imaging optical system according to a sixth embodiment of the present invention.
FIG. 12 is an aberration curve of the imaging optical system shown in FIG. 11

Hereinafter, preferred embodiments of the present invention will be described in detail based on the attached illustration drawings.

In describing the present invention below, terms referring to the components of the present invention are named in consideration of the function of each component, and should not be understood as limiting the technical components of the present invention.

In addition, throughout the specification, the fact that a certain configuration is 'connected' to another configuration includes not only cases where these configurations are 'directly connected', but also cases where they are 'indirectly connected' with another configuration in between. means that In addition, 'including' a certain component means that other components may be further included rather than excluding other components, unless specifically stated to the contrary.

In this specification, the first lens refers to the lens closest to the object (or subject), and the seventh lens refers to the lens closest to the image surface (or image sensor). In this specification, the radius of curvature of the lens, thickness, TTL (distance from the object side of the first lens to the image surface), 2IH (diagonal length of the image surface), IH (1/2 of 2HI), and focal length The unit is mm.

The thickness of the lens, the distance between lenses, and TTL are the distance from the optical axis of the lens. In addition, in the description of the shape of the lens, the shape that one side is convex means that the paraxial region of the surface is convex, and the shape that one side is concave means that the paraxial region of the surface is concave. Therefore, even if one surface of the lens is described as having a convex shape, the edge portion of the lens may be concave. Likewise, even if one side of the lens is described as having a concave shape, the edge of the lens may be convex.

The imaging optical system includes 7 lenses. For example, the imaging optical system may include a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens arranged sequentially from the object side. The first to seventh lenses are arranged at predetermined intervals. For example, the image side and object side of each lens do not contact the neighboring lens in the paraxial portion. Additionally, the f number of the imaging optical system may be 2.0 or less.

The first lens has refractive power. For example, the first lens has positive refractive power. The first lens has a convex shape on one side. For example, the first lens has a convex shape on the side of the object.

The first lens includes an aspherical surface. For example, both surfaces of the first lens may be aspherical. The first lens can be made of a material with high light transmittance and excellent processability. For example, the first lens may be made of plastic material. The first lens has a low refractive index. For example, the refractive index of the first lens may be less than 1.6.

The second lens has refractive power. For example, the second lens may have negative refractive power. The second lens has a convex shape on one side. For example, the second lens may have a convex shape on the side of the object.

The second lens includes an aspherical surface. For example, both sides of the second lens may be aspherical. The second lens can be made of a material with high light transmittance and excellent processability. For example, the second lens may be made of plastic material. The second lens has a higher refractive index than the first lens. For example, the refractive index of the second lens may be 1.6 or more. Additionally, the lower limit of the refractive index of the second lens can be further increased. For example, the refractive index of the second lens may be 1.67 or more.

The third lens has refractive power. For example, the third lens has positive refractive power. The third lens has a shape in which at least one side is convex. For example, the third lens may have a convex shape on the side of the object.

The third lens includes an aspherical surface. For example, both sides of the third lens may be aspherical. The third lens can be made of a material with high light transmittance and excellent processability. For example, the third lens may be made of plastic material. The third lens has a refractive index generally similar to that of the first lens. For example, the refractive index of the third lens may be less than 1.6.

The fourth lens has refractive power. For example, the fourth lens has negative refractive power. The fourth lens has a concave shape on one side. For example, the fourth lens may have a concave shape on the side of the object.

The fourth lens includes an aspherical surface. For example, both surfaces of the fourth lens may be aspherical. The fourth lens can be made of a material with high light transmittance and excellent processability. For example, the fourth lens may be made of plastic material. The fourth lens has a higher refractive index than the first lens. For example, the refractive index of the fourth lens may be 1.6 or more.

The fifth lens has refractive power. For example, the fifth lens may have positive or negative refractive power. The fifth lens has a convex shape on one side. For example, the fifth lens may have a convex shape on the side of the object. The fifth lens has a concave shape on one side. For example, the fifth lens may have a concave image side. The fifth lens may have a shape with an inflection point. For example, an inflection point may be formed on at least one of the object side and the image side of the fifth lens.

The fifth lens includes an aspherical surface. For example, both sides of the fifth lens may be aspherical. The fifth lens can be made of a material with high light transmittance and excellent processability. For example, the fifth lens may be made of plastic material. The fifth lens has a refractive index generally similar to that of the first lens. As an example, the refractive index of the fifth lens may be less than 1.6. As another example, the refractive index of the fifth lens may be greater than 1.5 and less than 1.6. The Abbe number of the fifth lens may be greater than 30 and less than 50.

The sixth lens has refractive power. For example, the sixth lens has positive refractive power. The sixth lens has a convex shape on one side. For example, the sixth lens may have a convex shape on the side of the object. The sixth lens may have a shape with an inflection point. For example, an inflection point may be formed on at least one of the object side and the image side of the sixth lens.

The sixth lens includes an aspherical surface. For example, both sides of the sixth lens may be aspherical. The sixth lens can be made of a material with high light transmittance and excellent processability. For example, the sixth lens may be made of plastic material. The sixth lens has a generally similar refractive index to the fifth lens. For example, the refractive index of the sixth lens may be less than 1.6.

The seventh lens has refractive power. For example, the seventh lens has negative refractive power. The seventh lens may have a concave shape on at least one side. For example, the seventh lens may have a concave shape on the side of the object. The seventh lens may have a shape with an inflection point. For example, one or more inflection points may be formed on at least one of the object side and the image side of the seventh lens.

The seventh lens includes an aspherical surface. For example, both sides of the seventh lens may be aspherical. The seventh lens can be made of a material with high light transmittance and excellent processability. For example, the seventh lens may be made of plastic material. The seventh lens has a generally similar refractive index to the sixth lens. For example, the refractive index of the seventh lens may be less than 1.6.

The first to seventh lenses include an aspherical surface as described above. The aspherical surface of the first to seventh lenses can be expressed by Equation 1.

In Equation 1, c is the reciprocal of the radius of curvature of the lens, k is the Conic constant, r is the distance from any point on the aspherical surface to the optical axis, A ~ J are aspherical constants, and Z (or SAG) is the aspherical surface It is the height in the direction of the optical axis from any point on the image to the vertex of the aspherical surface.

The imaging optical system further includes a filter, an image sensor, and an aperture.

The filter is disposed between the seventh lens and the image sensor. Filters can block some wavelengths of light. For example, a filter can block light in infrared wavelengths. The image sensor forms an image surface on which light refracted through the first to seventh lenses can be reflected. An image sensor converts optical signals into electrical signals. For example, an image sensor can convert optical signals incident on the image surface into electrical signals. The aperture is arranged to adjust the amount of light entering the lens. For example, the aperture may be disposed between the first lens and the second lens or between the second lens and the third lens.

The imaging optical system may satisfy one or more of the conditional expressions below.

[Conditional expression 1] 0 < f1/f < 2.0

[Conditional expression 2] 25 < V1-V2 < 45

[Conditional expression 3] -10 < V1-V3 < 10

[Conditional expression 4] 25 < V1-V4 < 45

[Conditional Expression 5] 0 < V1-V5 < 20

[Conditional Expression 6] -3.5 < f2/f < 0

[Conditional Expression 7] 1.5 < f3/f

[Conditional Expression 8] f4/f < 0

[Conditional Expression 9] f5/f < 0

[Conditional expression 10] 0 < f6/f

[Conditional Expression 11] f7/f < 0

[Conditional Expression 12] TTL/f < 1.4

[Conditional Expression 13] -1.0 < f1/f2 < 0

[Conditional Expression 14] -2.0 < f2/f3 < 0

[Conditional Expression 15] BFL/f < 0.4

[Conditional Expression 16] D12/f < 0.1

[Conditional Expression 17] SD5/IH < 0.6

[Conditional Expression 18] 0.7 < SD6/IH

[Conditional Expression 19] 0.8 < SD7/IH

[Conditional Expression 20] TTL/2IH < 0.730

[Conditional expression 21] 30 < V5 < 50

In the imaging optical system, the refractive power of the first lens is greater than that of the third lens, and the refractive power of the sixth lens is greater than that of the third lens. For example, the first lens, third lens, and sixth lens may all satisfy the following conditional expressions.

[Conditional Expression 22] 1/f3 < 1/f1

[Conditional Expression 23] 1/f3 < 1/f6

In the above conditional expression, f is the focal length of the imaging optical system, f1 is the focal length of the first lens, f2 is the focal length of the second lens, f3 is the focal length of the third lens, and f4 is the focal length of the fourth lens. , f5 is the focal length of the 5th lens, f6 is the focal length of the 6th lens, f7 is the focal length of the 7th lens, V1 is the Abbe number of the first lens, and V2 is the Abbe number of the second lens. , V3 is the Abbe number of the third lens, V4 is the Abbe number of the fourth lens, V5 is the Abbe number of the fifth lens, TTL is the distance from the object side to the image surface of the first lens, and BFL is the second lens. 7 is the distance from the image side of the lens to the image surface, D12 is the distance from the image side of the first lens to the object side of the second lens, SD5 is the effective radius of the fifth lens, and SD6 is the effective radius of the sixth lens. , SD7 is the effective radius of the 7th lens, and 2IH is the diagonal length of the image surface.

Conditional expression 1 is a condition for limiting the appropriate refractive power of the first lens. A first lens that is outside the numerical range of the corresponding conditional expression increases the focal length of the imaging optical system, making it difficult to miniaturize the imaging optical system. Conditional expressions 2 to 5 are conditions for reducing chromatic aberration of the imaging optical system. Conditional expressions 6 to 11 are conditions for limiting the appropriate refractive power of the second to seventh lenses, respectively. Lenses that fall outside the numerical range of the corresponding conditional expressions have too large or too small a refractive power, making aberration correction through each lens difficult. Conditional expressions 12 and 15 are conditions for miniaturization of the imaging optical system. An imaging optical system that exceeds the upper limit of the conditional expression is not suitable for use in a portable terminal because the distance from the object side of the first lens to the image surface is outside the range that can be mounted on a portable terminal, or the focal length of the imaging optical system is too short. Conditional expressions 13 and 14 are conditions for limiting the appropriate focal length of the first to third lenses. Lenses that fall outside the numerical range of the corresponding conditional expression have too large a refractive power and may worsen the aberration characteristics. Conditional expression 16 is a condition for reducing axial chromatic aberration through the first lens and the second lens. For example, if the distance between the first lens and the second lens exceeds the upper limit of the corresponding conditional expression, it is difficult to improve the axial chromatic aberration due to the deviation of the Abbe number of the first lens and the second lens. Conditional expressions 17 to 19 are conditions for reducing the flare phenomenon. If the effective radii of the fifth to seventh lenses deviate from the upper or lower limits of the corresponding conditional expression, the sweep angle of each lens may increase and the flare characteristics may deteriorate.

Next, an imaging optical system according to various embodiments will be described.

First, an imaging optical system according to a first embodiment will be described with reference to FIG. 1 .

The imaging optical system 100 includes a first lens 110, a second lens 120, a third lens 130, a fourth lens 140, a fifth lens 150, a sixth lens 160, and a seventh lens. Includes a lens 170.

The first lens 110 has a positive refractive power and has a shape where the object side is convex and the image side is concave. The second lens 120 has negative refractive power and has a shape where the side of the object is convex and the side of the image is concave. The third lens 130 has positive refractive power and has a shape in which the object side is convex and the image side is convex. The fourth lens 140 has negative refractive power and has a shape where the object side is concave and the image side is concave. The fifth lens 150 has a negative refractive power and has a shape where the object side is convex and the image side is concave. In addition, the fifth lens 150 has a shape in which inflection points are formed on the object side and the image side. The sixth lens 160 has positive refractive power and has a shape in which the object side is convex and the image side is convex. In addition, the sixth lens 160 has a shape in which inflection points are formed on the object side and the image side. The seventh lens 170 has negative refractive power and has a shape where the object side is concave and the image side is concave. In addition, the seventh lens 170 has a shape in which inflection points are formed on the object side and the image side.

The imaging optical system 100 further includes a filter 180 and an image sensor 190. The filter 180 is disposed between the seventh lens 170 and the image sensor 190. For reference, although not shown in the drawing, an aperture may be disposed between the second lens 120 and the third lens 130.

The imaging optical system configured as above exhibits aberration characteristics as shown in FIG. 2. Tables 1 and 2 show lens characteristics and aspherical values of the imaging optical system according to this embodiment.

Section number note radius of curvature Thickness/Distance refractive index Abesu S1 1st lens 2.31 0.912 1.544 56.1 S2 10.53 0.164 S3 2nd lens 6.94 0.234 1.671 19.3 S4 3.85 0.422 S5 Third lens 29.14 0.398 1.544 56.1 S6 -24.16 0.264 S7 4th lens -15.48 0.384 1.661 20.4 S8 60.01 0.421 S9 5th lens 6.03 0.391 1.568 37.4 S10 5.66 0.341 S11 6th lens 3.16 0.721 1.544 56.1 S12 -6.06 0.608 S13 7th lens -4.75 0.400 1.544 56.1 S14 2.67 0.305 S15 filter Infinity 0.210 1.514 64.1 S16 Infinity 0.505 top surface top surface Infinity 0.015

Ex.1 K A B C D E F G H J S1 -1.0366 0.0116 -0.0008 0.0048 -0.0062 0.0047 -0.0020 0.0005 -4.53E-05 0 S2 23.6958 -0.0234 0.0212 -0.0193 0.0153 -0.0096 0.0038 -0.0008 0.0001 0 S3 14.9297 -0.0630 0.0570 -0.0346 0.0148 -0.0034 -0.0002 0.0004 -0.0001 0 S4 0.1548 -0.0490 0.0678 -0.0816 0.1019 -0.0934 0.0551 -0.0183 0.0027 0 S5 0 -0.0423 0.0589 -0.1884 0.3228 -0.3302 0.1974 -0.0637 0.0086 0 S6 1.2398 -0.0405 0.0131 -0.0336 0.0382 -0.0292 0.0134 -0.0031 0.0003 0 S7 0.00E+00 -0.0791 0.0820 -0.1699 0.2105 -0.1653 0.0785 -0.0206 0.0023 0 S8 0.00E+00 -0.0733 0.0632 -0.0860 0.0773 -0.0452 0.0163 -0.0033 0.0003 0 S9 0.00E+00 -0.1024 0.0794 -0.0551 0.0259 -0.0082 0.0017 -0.0002 1.10E-05 0 S10 -64.3279 -0.1135 0.0639 -0.0370 0.0160 -0.0045 0.0008 -0.0001 3.26E-06 0 S11 -6.4594 -0.0209 0.0062 -0.0036 0.0001 0.0002 -4.09E-05 3.12E-06 -8.70E-08 0 S12 -96.2611 0.0152 0.0068 -0.0073 0.0021 -0.0003 2.36E-05 -9.62E-07 1.55E-08 0 S13 -8.2127 -0.0827 0.0327 -0.0059 0.0006 -3.90E-05 1.43E-06 -2.71E-08 1.86E-10 0 S14 -13.2198 -0.0455 0.0159 -0.0036 0.0005 -4.84E-05 2.91E-06 -1.07E-07 2.19E-09 0

The imaging optical system according to the second embodiment will be described with reference to FIG. 3. The imaging optical system 200 includes a first lens 210, a second lens 220, a third lens 230, and a fourth lens 240. , including the fifth lens 250, the sixth lens 260, and the seventh lens 270.

The first lens 210 has a positive refractive power and has a shape where the object side is convex and the image side is concave. The second lens 220 has negative refractive power and has a shape where the side of the object is convex and the side of the image is concave. The third lens 230 has positive refractive power and has a shape in which the object side is convex and the image side is convex. The fourth lens 240 has negative refractive power and has a shape where the object side is concave and the image side is concave. The fifth lens 250 has negative refractive power and has a shape where the side of the object is convex and the side of the image is concave. In addition, the fifth lens 250 has a shape in which inflection points are formed on the object side and the image side. The sixth lens 260 has positive refractive power and has a shape in which the object side is convex and the image side is convex. In addition, the sixth lens 260 has a shape in which inflection points are formed on the object side and the image side. The seventh lens 270 has negative refractive power and has a shape where the object side is concave and the image side is concave. In addition, the seventh lens 270 has a shape in which inflection points are formed on the object side and the image side.

The imaging optical system 200 further includes a filter 280 and an image sensor 290. The filter 280 is disposed between the seventh lens 270 and the image sensor 290. For reference, although not shown in the drawing, an aperture may be disposed between the second lens 220 and the third lens 230.

The imaging optical system configured as above exhibits aberration characteristics as shown in FIG. 4. Tables 3 and 4 show lens characteristics and aspherical values of the imaging optical system according to this embodiment.

Side number note radius of curvature Thickness/Distance refractive index Abesu S1 1st lens 2.31 0.902 1.544 56.1 S2 10.41 0.165 S3 2nd lens 6.90 0.230 1.671 19.3 S4 3.85 0.425 S5 Third lens 29.98 0.400 1.544 56.1 S6 -22.77 0.254 S7 4th lens -14.79 0.381 1.661 20.4 S8 76.35 0.433 S9 5th lens 5.97 0.385 1.568 37.4 S10 5.62 0.350 S11 6th lens 3.16 0.724 1.544 56.1 S12 -6.24 0.611 S13 7th lens -4.77 0.404 1.544 56.1 S14 2.67 0.305 S15 filter Infinity 0.210 1.514 64.1 S16 Infinity 0.506 top surface top surface Infinity 0.015

Ex.2 K A B C D E F G H J S1 -1.0458 0.0110 0.0016 0.0001 -0.0010 0.0013 -0.0008 0.0002 -2.34E-05 -1.89E-11 S2 23.3325 -0.0237 0.0220 -0.0210 0.0169 -0.0102 0.0039 -0.0008 0.0001 -1.89E-11 S3 14.9068 -0.0626 0.0550 -0.0321 0.0139 -0.0039 0.0005 0.0001 -4.75E-05 -1.89E-11 S4 0.1571 -0.0490 0.0681 -0.0849 0.1100 -0.1027 0.0608 -0.0201 0.0029 -1.89E-11 S5 0 -0.0435 0.0688 -0.2161 0.3638 -0.3653 0.2149 -0.0683 0.0091 -1.89E-11 S6 13.4162 -0.0370 0.0024 -0.0147 0.0143 -0.0093 0.0034 -0.0004 -4.30E-05 -1.89E-11 S7 0 -0.0731 0.0587 -0.1264 0.1595 -0.1292 0.0637 -0.0174 0.0020 -1.89E-11 S8 0 -0.0725 0.0621 -0.0871 0.0798 -0.0473 0.0173 -0.0035 0.0003 -1.89E-11 S9 0 -0.1048 0.0841 -0.0600 0.0290 -0.0096 0.0021 -0.0003 1.49E-05 -1.89E-11 S10 -63.2478 -0.1133 0.0633 -0.0349 0.0141 -0.0038 0.0006 -0.0001 2.56E-06 -1.89E-11 S11 -6.5212 -0.0205 0.0060 -0.0035 0.0001 0.0002 -3.94E-05 2.98E-06 -8.24E-08 -1.89E-11 S12 -98.4791 0.0159 0.0055 -0.0065 0.0019 -0.0003 2.00E-05 -7.81E-07 1.18E-08 -1.89E-11 S13 -7.8013 -0.0814 0.0318 -0.0057 0.0006 -3.69E-05 1.34E-06 -2.46E-08 1.48E-10 -1.89E-11 S14 -13.1752 -0.0450 0.0157 -0.0036 0.0005 -0.0001 3.37E-06 -1.37E-07 3.16E-09 -3.20E-11

An imaging optical system according to a third embodiment will be described with reference to FIG. 5. The imaging optical system 300 includes a first lens 310, a second lens 320, a third lens 330, and a fourth lens 340. , including the fifth lens 350, the sixth lens 360, and the seventh lens 370.

The first lens 310 has positive refractive power and has a shape where the object side is convex and the image side is concave. The second lens 320 has negative refractive power and has a shape where the side of the object is convex and the side of the image is concave. The third lens 330 has positive refractive power and has a shape where the object side is convex and the image side is concave. The fourth lens 340 has negative refractive power and has a shape where the object side is concave and the image side is concave. The fifth lens 350 has positive refractive power and has a shape where the object side is convex and the image side is concave. In addition, the fifth lens 350 has a shape in which inflection points are formed on the object side and the image side. The sixth lens 360 has positive refractive power and has a shape in which the object side is convex and the image side is convex. In addition, the sixth lens 360 has a shape in which inflection points are formed on the object side and the image side. The seventh lens 370 has negative refractive power and has a shape where the object side is concave and the image side is concave. In addition, the seventh lens 370 has a shape in which inflection points are formed on the object side and the image side.

The imaging optical system 300 further includes a filter 380 and an image sensor 390. The filter 380 is disposed between the seventh lens 370 and the image sensor 390. For reference, although not shown in the drawing, an aperture may be disposed between the second lens 320 and the third lens 330.

The imaging optical system configured as above exhibits aberration characteristics as shown in FIG. 6. Tables 5 and 6 show the lens characteristics and aspherical values of the imaging optical system according to this embodiment.

Section number note radius of curvature Thickness/Distance refractive index Abesu S1 1st lens 2.31 0.872 1.544 56.1 S2 9.70 0.188 S3 2nd lens 6.75 0.230 1.671 19.3 S4 3.80 0.489 S5 Third lens 16.19 0.385 1.544 56.1 S6 167.06 0.300 S7 4th lens -23.80 0.305 1.661 20.4 S8 40.38 0.366 S9 5th lens 5.35 0.370 1.568 37.4 S10 5.32 0.395 S11 6th lens 3.24 0.686 1.544 56.1 S12 -6.56 0.717 S13 7th lens -3.58 0.400 1.544 56.1 S14 3.42 0.305 S15 filter Infinity 0.210 1.514 64.1 S16 Infinity 0.467 top surface top surface Infinity 0.015

Ex.3 K A B C D E F G H J S1 -1.1399 0.0126 -0.0026 0.0080 -0.0100 0.0073 -0.0031 0.0007 -0.0001 0 S2 17.5707 -0.0266 0.0136 -0.0013 -0.0051 0.0039 -0.0014 0.0002 -1.65E-05 0 S3 13.9756 -0.0693 0.0468 0.0053 -0.0362 0.0329 -0.0152 0.0037 -0.0004 0 S4 0.8385 -0.0479 0.0299 0.0494 -0.1079 0.1034 -0.0542 0.0149 -0.0016 0 S5 0 -0.0461 0.0540 -0.1587 0.2603 -0.2573 0.1493 -0.0469 0.0062 0 S6 -7.5340 -0.0448 0.0274 -0.0781 0.1061 -0.0865 0.0412 -0.0104 0.0011 0 S7 0 -0.0764 0.0778 -0.1673 0.1988 -0.1446 0.0632 -0.0151 0.0015 0 S8 0 -0.0847 0.0920 -0.1359 0.1217 -0.0680 0.0232 -0.0044 0.0004 0 S9 0 -0.1262 0.1233 -0.0966 0.0501 -0.0176 0.0040 -0.0005 3.07E-05 0 S10 -54.7889 -0.1208 0.0816 -0.0462 0.0181 -0.0049 0.0009 -0.0001 4.45E-06 0 S11 -8.7794 -0.0128 -0.0022 0.0010 -0.0010 0.0004 -0.0001 4.45E-06 -1.33E-07 0 S12 -40.2521 0.0295 -0.0189 0.0049 -0.0009 0.0002 -1.76E-05 1.16E-06 -3.12E-08 0 S13 -3.6141 -0.0550 0.0087 0.0019 -0.0007 0.0001 -6.62E-06 2.36E-07 -3.47E-09 0 S14 -15.7838 -0.0378 0.0096 -0.0013 0.0001 -1.72E-06 -1.76E-07 1.40E-08 -4.05E-10 4.26E-12

An imaging optical system according to a fourth embodiment will be described with reference to FIG. 7. The imaging optical system 400 includes a first lens 410, a second lens 420, a third lens 430, and a fourth lens 440. , including the fifth lens 450, the sixth lens 460, and the seventh lens 470.

The first lens 410 has positive refractive power and has a shape where the object side is convex and the image side is concave. The second lens 420 has a negative refractive power and has a shape where the object side is convex and the image side is concave. The third lens 430 has positive refractive power and has a shape in which the object side is convex and the image side is convex. The fourth lens 440 has negative refractive power and has a shape where the object side is concave and the image side is concave. The fifth lens 450 has negative refractive power and has a shape where the object side is convex and the image side is concave. In addition, the fifth lens 450 has a shape in which inflection points are formed on the object side and the image side. The sixth lens 460 has positive refractive power and has a shape where the object side is convex and the image side is concave. In addition, the sixth lens 460 has a shape in which inflection points are formed on the object side and the image side. The seventh lens 470 has negative refractive power and has a shape where the object side is concave and the image side is concave. In addition, the seventh lens 470 has a shape in which inflection points are formed on the object side and the image side.

The imaging optical system 400 further includes a filter 480 and an image sensor 490. The filter 480 is disposed between the seventh lens 470 and the image sensor 490. For reference, although not shown in the drawing, an aperture may be disposed between the second lens 420 and the third lens 430.

The imaging optical system configured as above exhibits aberration characteristics as shown in FIG. 8. Tables 7 and 8 show lens characteristics and aspherical values of the imaging optical system according to this embodiment.

Side number note radius of curvature Thickness/Distance refractive index Abesu S1 1st lens 2.723 1.100 1.544 56.1 S2 12.203 0.181 S3 2nd lens 8.384 0.230 1.671 19.3 S4 4.498 0.529 S5 Third lens 83.525 0.424 1.544 56.1 S6 -31.911 0.232 S7 4th lens -40.873 0.408 1.661 20.4 S8 497.247 0.678 S9 5th lens 6.912 0.373 1.568 37.4 S10 5.807 0.443 S11 6th lens 2.544 0.541 1.544 56.1 S12 6.584 1.354 S13 7th lens -4.071 0.420 1.544 56.1 S14 7.701 0.377 S15 filter Infinity 0.210 1.514 64.2 S16 Infinity 0.345 top surface top surface Infinity -0.015

Ex.4 K A B C D E F G H J S1 -1.0394 0.0040 0.0069 -0.0084 0.0069 -0.0036 0.0012 -0.0003 3.23E-05 -1.74E-06 S2 21.6009 -0.0171 0.0046 0.0082 -0.0127 0.0089 -0.0037 0.0009 -0.0001 7.09E-06 S3 15.9987 -0.0525 0.0325 0.0037 -0.0232 0.0211 -0.0103 0.0030 -0.0005 3.06E-05 S4 1.0581 -0.0412 0.0340 -0.0111 0.0039 -0.0057 0.0059 -0.0029 0.0007 -0.0001 S5 0 -0.0210 -0.0180 0.0475 -0.0705 0.0651 -0.0374 0.0129 -0.0025 0.0002 S6 -76.4723 -0.0373 0.0235 -0.0503 0.0666 -0.0527 0.0260 -0.0079 0.0013 -0.0001 S7 0 -0.0410 0.0064 -0.0081 0.0068 -0.0022 -0.0003 0.0004 -0.0001 1.26E-05 S8 0 -0.0354 0.0130 -0.0145 0.0106 -0.0045 0.0011 -0.0001 -7.15E-06 1.59E-06 S9 0 -0.0625 0.0399 -0.0218 0.0081 -0.0022 0.0004 -0.0001 0.0000 -1.37E-07 S10 -99.0000 -0.0603 0.0241 -0.0076 0.0016 -0.0002 2.98E-05 -3.23E-06 2.10E-07 -5.68E-09 S11 -7.2394 0.0102 -0.0102 0.0021 -0.0004 0.0001 -5.72E-06 3.13E-07 -9.05E-09 1.08E-10 S12 -27.2182 0.0362 -0.0182 0.0039 -0.0006 0.0001 -4.38E-06 2.05E-07 -5.44E-09 6.16E-11 S13 -4.2405 -0.0338 0.0065 -0.0004 1.56E-06 1.38E-06 -8.01E-08 1.82E-09 -1.07E-11 -1.27E-13 S14 -54.8281 -0.0218 0.0032 -0.0003 1.25E-05 -3.05E-07 1.15E-08 -8.25E-10 2.96E-11 -3.74E-13

The imaging optical system according to the fifth embodiment will be described with reference to FIG. 9. The imaging optical system 500 includes a first lens 510, a second lens 520, a third lens 530, and a fourth lens 540. , including a fifth lens 550, a sixth lens 560, and a seventh lens 570.

The first lens 510 has positive refractive power and has a shape where the object side is convex and the image side is concave. The second lens 520 has negative refractive power and has a shape where the object side is convex and the image side is concave. The third lens 530 has positive refractive power and has a shape in which the object side is convex and the image side is convex. The fourth lens 540 has negative refractive power and has a shape where the object side is concave and the image side is concave. The fifth lens 550 has negative refractive power and has a shape where the object side is convex and the image side is concave. In addition, the fifth lens 550 has a shape in which inflection points are formed on the object side and the image side. The sixth lens 560 has positive refractive power and has a shape where the object side is convex and the image side is concave. In addition, the sixth lens 560 has a shape in which inflection points are formed on the object side and the image side. The seventh lens 570 has negative refractive power and has a shape where the object side is concave and the image side is concave. In addition, the seventh lens 570 has a shape in which inflection points are formed on the object side and the image side.

The imaging optical system 500 further includes a filter 580 and an image sensor 590. The filter 580 is disposed between the seventh lens 570 and the image sensor 590. For reference, although not shown in the drawing, an aperture may be disposed between the second lens 520 and the third lens 530.

The imaging optical system configured as above exhibits aberration characteristics as shown in FIG. 10. Table 9 and Table 10 show lens characteristics and aspherical values of the imaging optical system according to this embodiment.

Section number note radius of curvature Thickness/Distance refractive index Abesu S1 1st lens 2.7185076 1.092 1.544 56.1 S2 12.76 0.175 S3 2nd lens 8.66 0.230 1.671 19.3 S4 4.58 0.542 S5 Third lens 58.30 0.437 1.544 56.1 S6 -37.343513 0.233 S7 4th lens -39.38 0.455 1.639 23.5 S8 197.62 0.629 S9 5th lens 6.51 0.370 1.568 37.4 S10 4.86 0.417 S11 6th lens 2.50 0.544 1.544 56.1 S12 7.54 1.368 S13 7th lens -4.08 0.420 1.544 56.1 S14 7.41 0.377 S15 filter Infinity 0.210 1.514 64.2 S16 Infinity 0.347 top surface top surface Infinity -0.015

Ex.5 K A B C D E F G H J S1 -1.0355 0.0008 0.0147 -0.0193 0.0161 -0.0085 0.0029 -0.0006 0.0001 -3.66E-06 S2 23.2430 -0.0191 0.0100 0.0009 -0.0062 0.0051 -0.0023 0.0006 -0.0001 4.77E-06 S3 16.0208 -0.0571 0.0446 -0.0141 -0.0065 0.0106 -0.0060 0.0018 -0.0003 2.02E-05 S4 0.9155 -0.0438 0.0385 -0.0132 -0.0020 0.0049 -0.0023 0.0005 -1.72E-05 -4.19E-06 S5 0 -0.0212 -0.0159 0.0393 -0.0520 0.0426 -0.0217 0.0067 -0.0011 0.0001 S6 -43.9004 -0.0442 0.0384 -0.0699 0.0811 -0.0581 0.0263 -0.0074 0.0012 -0.0001 S7 0 -0.0412 0.0034 0.0035 -0.0134 0.0170 -0.0110 0.0039 -0.0007 0.0001 S8 0 -0.0371 0.0171 -0.0170 0.0098 -0.0028 0.0001 0.0002 -4.53E-05 3.78E-06 S9 0 -0.0761 0.0558 -0.0344 0.0147 -0.0045 0.0009 -0.0001 9.80E-06 -3.30E-07 S10 -75.9915 -0.0668 0.0292 -0.0101 0.0023 -0.0004 0.0001 -4.85E-06 2.85E-07 -7.22E-09 S11 -8.2269 0.0131 -0.0136 0.0036 -0.0008 0.0001 -1.04E-05 5.57E-07 -1.59E-08 1.90E-10 S12 -38.3867 0.0373 -0.0206 0.0051 -0.0008 0.0001 -7.88E-06 3.83E-07 -1.03E-08 1.18E-10 S13 -3.1329 -0.0341 0.0063 -0.0004 -7.92E-07 1.14E-06 -4.71E-08 1.78E-10 2.87E-11 -5.13E-13 S14 -42.1372 -0.0248 0.0041 -0.0004 2.77E-05 -1.22E-06 3.46E-08 -6.33E-10 9.25E-12 -1.06E-13

An imaging optical system according to the sixth embodiment will be described with reference to FIG. 11. The imaging optical system 600 includes a first lens 610, a second lens 620, a third lens 630, and a fourth lens 640. , including a fifth lens 650, a sixth lens 660, and a seventh lens 670.

The first lens 610 has positive refractive power and has a shape where the object side is convex and the image side is concave. The second lens 620 has a negative refractive power and has a shape where the object side is convex and the image side is concave. The third lens 630 has positive refractive power and has a shape in which the object side is convex and the image side is convex. The fourth lens 640 has negative refractive power and has a shape in which the object side is concave and the image side is convex. The fifth lens 650 has positive refractive power and has a shape where the object side is convex and the image side is concave. In addition, the fifth lens 650 has a shape in which inflection points are formed on the object side and the image side. The sixth lens 660 has positive refractive power and has a shape where the object side is convex and the image side is concave. In addition, the sixth lens 660 has a shape in which inflection points are formed on the object side and the image side. The seventh lens 670 has negative refractive power and has a shape where the object side is concave and the image side is concave. In addition, the seventh lens 670 has a shape in which inflection points are formed on the object side and the image side.

The imaging optical system 600 further includes a filter 680 and an image sensor 690. The filter 680 is disposed between the seventh lens 670 and the image sensor 690. For reference, although not shown in the drawing, an aperture may be disposed between the second lens 620 and the third lens 630.

The imaging optical system configured as above exhibits aberration characteristics as shown in FIG. 12. Tables 11 and 12 show lens characteristics and aspherical values of the imaging optical system according to this embodiment.

Side number note radius of curvature Thickness/Distance refractive index Abesu S1 1st lens 2.67 1.031 1.544 56.1 S2 9.43 0.200 S3 2nd lens 6.95 0.230 1.680 18.4 S4 4.29 0.622 S5 Third lens 59.38986 0.437 1.544 56.1 S6 -50.84 0.264 S7 4th lens -23.50 0.326 1.680 18.4 S8 -61.66 0.571 S9 5th lens 6.42 0.359 1.568 37.4 S10 6.69 0.493 S11 6th lens 3.06 0.552 1.544 56.1 S12 9.80 1.430 S13 7th lens -3.48 0.403 1.544 56.1 S14 10.26 0.181 S15 filter Infinity 0.210 1.514 64.2 S16 Infinity 0.509 top surface top surface Infinity 0.012

Ex.6 K A B C D E F G H J S1 -1.0111 0.0031 0.0115 -0.0176 0.0170 -0.0102 0.0038 -0.0009 0.0001 -6.32E-06 S2 14.6338 -0.0181 0.0087 -0.0053 0.0039 -0.0024 0.0010 -0.0002 3.43E-05 -2.02E-06 S3 13.0489 -0.0453 0.0301 -0.0165 0.0139 -0.0111 0.0059 -0.0019 0.0003 -2.53E-05 S4 2.0700 -0.0302 0.0190 0.0095 -0.0239 0.0234 -0.0137 0.0048 -0.0010 0.0001 S5 0 -0.0158 -0.0302 0.0716 -0.1026 0.0914 -0.0512 0.0176 -0.0034 0.0003 S6 94.2471 -0.0214 -0.0101 0.0093 -0.0072 0.0054 -0.0031 0.0011 -0.0002 1.63E-05 S7 0 -0.0167 -0.0437 0.0720 -0.0791 0.0568 -0.0259 0.0072 -0.0011 0.0001 S8 0 -0.0186 -0.0236 0.0334 -0.0305 0.0182 -0.0069 0.0016 -0.0002 1.17E-05 S9 0 -0.0396 0.0203 -0.0108 0.0041 -0.0011 0.0002 -2.52E-05 1.79E-06 -5.46E-08 S10 -55.6301 -0.0479 0.0210 -0.0082 0.0024 -0.0005 0.0001 -7.14E-06 3.78E-07 -8.43E-09 S11 -7.3401 0.0023 -0.0046 0.0004 1.39E-06 -2.88E-06 3.40E-07 -2.51E-08 1.01E-09 -1.63E-11 S12 -70.2827 0.0258 -0.0110 0.0019 -0.0002 1.02E-05 -2.06E-07 -1.08E-08 7.73E-10 -1.41E-11 S13 -5.4006 -0.0324 0.0065 -0.0006 0.0001 -6.11E-06 4.47E-07 -1.95E-08 4.53E-10 -4.35E-12 S14 -81.9062 -0.0174 0.0025 -0.0002 1.41E-05 -1.05E-06 7.83E-08 -3.60E-09 8.34E-11 -7.60E-13

Table 13 shows characteristic values of the imaging optical system according to the first to sixth embodiments.

note Embodiment 1 Second embodiment Third embodiment Embodiment 4 Embodiment 5 Embodiment 6 f 5.4400 5.4400 5.5000 6.7900 6.7900 6.7700 f1 5.2118 5.2360 5.3400 6.1671 6.0930 6.4870 f2 -13.136 -13.269 -13.240 -14.973 -14.655 -16.875 f3 24.259 23.771 32.805 42.349 41.763 50.247 f4 -18.415 -18.540 -22.408 -56.614 -50.900 -55.460 f5 -264.430 -276.040 469.354 -72.648 -36.671 189.158 f6 3.9103 3.9450 4.0730 7.2520 6.5810 7.9250 f7 -3.0703 -3.0755 -3.1397 -4.8170 -4.7618 -4.7070 f12 7.4920 7.5199 7.7610 9.1670 4.8690 9.2468 TTL 6.6945 6.7000 6.7000 7.8300 7.8300 7.8298 BFL 1.0349 1.0360 0.9966 0.9175 0.9188 0.9120 FOV 80.0 80.0 80.0 82.0 82.0 82.0 IH 4.6500 4.6500 4.6500 6.0070 6.0070 6.0070 SD5 2.2950 2.2961 2.2430 3.0737 3.0639 2.9890 SD6 3.3180 3.3176 3.1810 4.2745 4.1594 4.2990 SD7 4.1960 4.2461 4.1426 5.0657 4.9940 5.1200

Additionally, the imaging optical system according to the present invention may generally have the following optical characteristics. For example, the total length (TTL) of the imaging optical system is determined in the range of 5.7 to 8.8 mm, the total focal length is determined in the range of 4.8 to 7.4 mm, and the focal length of the first lens is determined in the range of 5.0 to 6.7 mm. The focal length of the second lens is determined in the range of -20 to -10 mm, the focal length of the third lens is determined in the range of 20 to 60 mm, and the focal length of the fourth lens is determined in the range less than -15 mm. , the focal length of the fifth lens is determined in the range of greater than 100 mm or less than -30 mm, the focal length of the sixth lens is determined in the range of 3.0 to 9.0 mm, and the focal length of the seventh lens is -5.6 to -2.2 mm. It is determined by the scope. In addition, the field of view (FOV) of the imaging optical system is determined in the range of 78 to 86 degrees. Table 14 shows the conditional expression values of the imaging optical system according to the first to sixth embodiments.

conditional expression Embodiment 1 Second embodiment Third embodiment Embodiment 4 Embodiment 5 Embodiment 6 f1/f 0.9581 0.9625 0.9709 0.9083 0.8973 0.9582 V1-V2 36.85 36.85 36.85 36.84 36.84 37.67 V1-V3 0 0 0 -0.01 -0.01 -0.01 V1-V4 35.75 35.75 35.75 35.74 32.57 37.67 V1-V5 18.74 18.74 18.74 18.73 18.73 18.73 f2/f -2.4147 -2.4392 -2.4073 -2.2051 -2.1583 -2.4926 f3/f 4.4594 4.3697 5.9645 6.2369 6.1507 7.4219 f4/f -3.3851 -3.4081 -4.0742 -8.3378 -7.4963 -8.1920 f5/f -48.608 -50.743 85.337 -10.699 -5.401 27.941 f6/f 0.7188 0.7252 0.7405 1.0680 0.9692 1.1706 f7/f -0.5644 -0.5653 -0.5709 -0.7094 -0.7013 -0.6953 TTL/f 1.2306 1.2316 1.2182 1.1532 1.1532 1.1565 f1/f2 -0.3968 -0.3946 -0.4033 -0.4119 -0.4158 -0.3844 f2/f3 -0.5415 -0.5582 -0.4036 -0.3536 -0.3509 -0.3358 BFL/f 0.1902 0.1904 0.1812 0.1351 0.1353 0.1347 D12/f 0.0302 0.0304 0.0341 0.0267 0.0257 0.0296 SD5/IH 0.4935 0.4938 0.4824 0.5117 0.5101 0.4976 SD6/IH 0.7135 0.7135 0.6841 0.7116 0.6924 0.7157 SD7/IH 0.9024 0.9131 0.8909 0.8433 0.8314 0.8523

The present invention is not limited to the embodiments described above, and those of ordinary skill in the technical field to which the present invention pertains can make any changes without departing from the gist of the technical idea of the present invention as set forth in the following claims. It can be implemented with various changes. For example, various features described in the above-described embodiments may be applied in combination to other embodiments unless explicitly stated to the contrary.

100, 200, 300, 400, 500, 600 imaging optical system
110, 210, 310, 410, 510, 610 1st lens
120, 220, 320, 420, 520, 620 2nd lens
130, 230, 330, 430, 530, 630 3rd lens
140, 240, 340, 440, 540, 640 4th lens
150, 250, 350, 450, 550, 650 5th lens
160, 260, 360, 460, 560, 660 6th lens
170, 270, 370, 470, 570, 670 7th lens
180, 280, 380, 480, 580, 680 (infrared blocking) filters
190, 290, 390, 490, 590, 690 image sensor or upper surface

Claims (15)

A first lens having a convex object side and a concave image side;
A second lens that has refractive power and has a convex shape on the side of the object;
a third lens having positive refractive power;
a fourth lens having negative refractive power;
a fifth lens having positive refractive power;
A sixth lens with positive refractive power and a concave image side; and
A seventh lens having refractive power;
Including,
The first to seventh lenses are sequentially arranged from the object side,
An imaging optical system that satisfies the following conditional expressions.
-2.0 < f2/f3 < 0
TTL/f < 1.4
-3.5 < f2/f < 0
(In the above conditional expression, f is the focal length of the imaging optical system, f2 is the focal length of the second lens, f3 is the focal length of the third lens, and TTL is the distance from the object side to the image surface of the first lens. am) delete According to paragraph 1,
The third lens is an imaging optical system in which the image side has a convex shape. delete According to paragraph 1,
The sixth lens is an imaging optical system in which the side of the object has a convex shape. delete According to paragraph 1,
The seventh lens is an imaging optical system in which the image side has a concave shape. A first lens having positive refractive power and having a concave image side;
A second lens having negative refractive power and having a convex side surface of the object;
a third lens having refractive power;
A fourth lens that has refractive power and has a concave image side;
a fifth lens having positive refractive power;
A sixth lens having positive refractive power; and
a seventh lens having negative refractive power;
Including,
The first to seventh lenses are sequentially arranged from the object side,
An imaging optical system that satisfies the following conditional expressions.
1.5 < Nd5 < 1.6
4.8 mm ≤ f ≤ 7.4 mm
-3.5 < f2/f < 0
(In the above conditional expression, Nd5 is the refractive index of the fifth lens, f is the focal length of the imaging optical system, and f2 is the focal length of the second lens) According to clause 8,
The fourth lens is an imaging optical system having negative refractive power. According to clause 8,
An imaging optical system that satisfies the following conditional expression.
0 < f1/f < 2.0
(In the above conditional expression, f1 is the focal length of the first lens) delete According to clause 8,
An imaging optical system that satisfies the following conditional expression.
-1.0 < f1/f2 < 0
(In the above conditional expression, f1 is the focal length of the first lens) According to clause 8,
An imaging optical system with an f-number of 2.0 or less. According to clause 8,
An imaging optical system that satisfies the following conditional expression.
BFL/f < 0.4
(In the above conditional expression, BFL is the distance from the image side of the seventh lens to the image surface) According to clause 8,
An imaging optical system that satisfies the following conditional expression.
D12/f < 0.1
(In the above conditional expression, D12 is the distance from the image side of the first lens to the object side of the second lens)